/**
 * 
 */
package org.jft.datamodel.database;

import java.sql.Types;

import org.hibernate.dialect.Dialect;
import org.hibernate.dialect.function.SQLFunctionTemplate;
import org.hibernate.dialect.function.StandardSQLFunction;
import org.hibernate.dialect.function.VarArgsSQLFunction;
import org.hibernate.type.IntegerType;
import org.hibernate.type.StringType;


public class SQLiteDialect extends Dialect {
    public SQLiteDialect() {
        super();
        registerColumnType(Types.TINYINT, "integer");
        registerColumnType(Types.SMALLINT, "integer");
        registerColumnType(Types.INTEGER, "integer");
        registerColumnType(Types.BIGINT, "integer");
        registerColumnType(Types.FLOAT, "real");
        registerColumnType(Types.REAL, "real");
        registerColumnType(Types.DOUBLE, "real");
        registerColumnType(Types.NUMERIC, "numeric");
        registerColumnType(Types.DECIMAL, "numeric");
        registerColumnType(Types.CHAR, "text");
        registerColumnType(Types.VARCHAR, "text");
        registerColumnType(Types.LONGVARCHAR, "text");
        registerColumnType(Types.DATE, "numeric");
        registerColumnType(Types.TIME, "numeric");
        registerColumnType(Types.TIMESTAMP, "numeric");
        registerColumnType(Types.NULL, "null");
        registerColumnType(Types.BLOB, "blob");
        registerColumnType(Types.CLOB, "text");
        registerColumnType(Types.BOOLEAN, "integer");


        registerFunction("concat", new VarArgsSQLFunction(new StringType(), "", "||", ""));
        registerFunction("mod", new SQLFunctionTemplate(new IntegerType(), "?1 % ?2"));
        registerFunction("substr", new StandardSQLFunction("substr", new StringType()));
        registerFunction("substring", new StandardSQLFunction("substr", new StringType()));
    }


    public boolean supportsIdentityColumns() {
        return true;
    }


    /*
     public boolean supportsInsertSelectIdentity() {
     return true; // As specify in NHibernate dialect
     }
     */


    public boolean hasDataTypeInIdentityColumn() {
        return false; // As specify in NHibernate dialect
    }


    /*
     public String appendIdentitySelectToInsert(String insertString) {
     return new StringBuffer(insertString.length()+30). // As specify in NHibernate dialect
     append(insertString).
     append("; ").append(getIdentitySelectString()).
     toString();
     }
     */


    public String getIdentityColumnString() {
        // return "integer primary key autoincrement";
        return "integer";
    }


    public String getIdentitySelectString() {
        return "select last_insert_rowid()";
    }


    public boolean supportsLimit() {
        return true;
    }


    public String getLimitString(String query, boolean hasOffset) {
        return new StringBuffer(query.length() + 20).append(query)
            .append(hasOffset ? " limit ? offset ?" : " limit ?").toString();
    }


    public boolean supportsTemporaryTables() {
        return true;
    }


    public String getCreateTemporaryTableString() {
        return "create temporary table if not exists";
    }


    public boolean dropTemporaryTableAfterUse() {
        return false;
    }


    public boolean supportsCurrentTimestampSelection() {
        return true;
    }


    public boolean isCurrentTimestampSelectStringCallable() {
        return false;
    }


    public String getCurrentTimestampSelectString() {
        return "select current_timestamp";
    }


    public boolean supportsUnionAll() {
        return true;
    }


    public boolean hasAlterTable() {
        return false; // As specify in NHibernate dialect
    }


    public boolean dropConstraints() {
        return false;
    }


    public String getAddColumnString() {
        return "add column";
    }


    public String getForUpdateString() {
        return "";
    }


    public boolean supportsOuterJoinForUpdate() {
        return false;
    }


    public String getDropForeignKeyString() {
        throw new UnsupportedOperationException(
            "No drop foreign key syntax supported by SQLiteDialect");
    }


    public String getAddForeignKeyConstraintString(String constraintName, String[] foreignKey,
                                                   String referencedTable, String[] primaryKey,
                                                   boolean referencesPrimaryKey) {
        throw new UnsupportedOperationException(
            "No add foreign key syntax supported by SQLiteDialect");
    }


    public String getAddPrimaryKeyConstraintString(String constraintName) {
        throw new UnsupportedOperationException(
            "No add primary key syntax supported by SQLiteDialect");
    }


    public boolean supportsIfExistsBeforeTableName() {
        return true;
    }


    public boolean supportsCascadeDelete() {
        return false;
    }
}
